Noob dérailleur help please.

Hey guys! I ride mountain bike trails in Miami. I rode both days this weekend. I have noticed a bit of noise when I crank at cleaning time. Seems one of the derailleur spindles is a bit rough also. I'm not sure if that's fixable. Also the new chain I had installed at my local bike shop is very noisy when I crank. Full of dirt/debris. Is this normal? Can I fix these issues myself? What cleaning products do you recommend?

OK, it's a good bike, not a Walmart special. Are you riding in sand or sandy conditions? If the problem is in the rear derailleur, first check that nothing is bent or mis-aligned and that the shifting is good. It may be as simple as a cable tension adjustment. If the alignment is good, the pulleys come out relatively easy for disassembly and cleaning.

They fill holes there with sugar sand. So yeah, my entire bottom of the bike is brown and white dust. I know for a fact that the middle spindle is rough. Also the chain sounds horrible. The crank itself is fine. I just don't want to take everything apart. And it was perfectly tuned about a month ago. I have ridden 10 times since then.

you mentioned a "new chain", IME when a new chain is installed on a used set of cogs and chainrings, it's pretty sure to make more noise than the previous chain. and will likely do so for a while. the jockey wheels may also be in on the conspiracy.

The new chain I purchased does in fact have the removable link. I would like to do this myself, considering I ride these conditions twice a week now. So maintenance could get a little pricey if it's in the shop every other week. Is there any way to fully take apart the center spindle in the x5 derailleur? I would love to remove whatever is causing it to stick. By the way, thank you guys for the advice!